Scientists at Harvard University say they've created a horde of more than a thousand small robots capable of working together to accomplish tasks.
The swarm, working in concert without needing a central guiding intelligence, can move and come together to create letters in the alphabet, five-pointed stars and other similarly complex designs, they say.
"No one had really built a swarm of this size before, where everyone works together to achieve a goal," says project leader and robotics scientist Michael Rubenstein.
Future uses for such self-assembling swarms could include planetary exploration, oil spill cleanups, deep-sea operations and military surveillance, the researchers say.
The robot swarm is inspired by similar behavior in nature, where creatures such as birds and fish come together in flocks or schools, and social insects like ants, bees and termites collaborate to carry out complicated tasks without any one single individual taking charge.
"The beauty of biological systems is that they are elegantly simple and yet, in large numbers, accomplish the seemingly impossible," says Harvard computer scientist Radhika Nagpal.
To recreate that ability in their robot swarm, the Harvard researchers created a programming algorithm that allowed individual robots in the swarm to locate each other while cooperating in a task without needing constant instructions.
The programming gives each individual robot three abilities: the ability to move around the edge of a group, track its own distance from its starting point, and maintain the knowledge of its own relative position.
Any designed task begins with a single instruction beamed simultaneously to every robot in the swarm via infrared, after which, like a flash mob, the robots can communicate with each other through their own infrared signals.
They can even correct for mistakes, the researchers point out; if a robot moves off its course or if a traffic jam starts to develop, robots nearby can sense the problem and work together to get things back on course.
The Harvard robots, dubbed Kilobots, are each about the size of a penny and can be built for $14 worth of parts.
In theory, the researchers say, there is no upper limit to the number of robots in a swarm or its size, complexity or scale.
"It could automatically change shape to adapt to the task at hand," Rubenstein says. "You could have them build other robots out of themselves."
The Harvard researchers have described the development of their robot swarm in the journal Science.
